Refueling check valve for compressed natural gas powered vehicles

Abstract

A refueling check valve assembly which provides for rapid, efficient, and safe refueling of compressed natural gas powered vehicles is provided and includes a receptacle adapted to mate with a fuel supply nozzle and a valve body having first and second gas flow passages therethrough. The respective first ends of the first and second gas flow passages communicate with the receptacle, while the respective second ends of the first and second gas flow passages are adapted to communicate with a fuel storage vessel, typically through a fuel supply line. A check valve is positioned in the first gas flow passage of the valve body and is normally biased into a closed position to prevent the flow of gas through the first gas flow passage. The check valve opens in response to a flow of fuel under pressure, permitting the flow of gas to the fuel storage vessel. A by-pass valve is also provided in the second gas flow passage in the valve body for depressurizing the fuel system prior to servicing.

What is claimed is: 
     
       1. A refueling check valve assembly for a compressed natural gas vehicle comprising: a) a receptacle adapted to mate with a fuel supply nozzle;   b) a valve body having first and second gas flow passages therethrough, the respective first ends of said first and second gas flow passages communicating with said receptacle, and the respective second ends of said first and second gas flow passages adapted to communicate with a fuel storage vessel;   c) a check valve in said first gas flow passage of said valve body, said check valve being normally biased into a closed position to prevent the flow of gas through said first gas flow passage and which opens in response to a flow of fuel under pressure; and   d) a by-pass valve in said second gas flow passage in said valve body, said by-pass valve being operable to permit a flow of gas from said fuel storage vessel through said receptacle.   
     
     
       2. The refueling check valve of claim 1 in which said receptacle includes a filter for removing particulate matter from the fuel. 
     
     
       3. The refueling check valve of claim 1 including a dust cap adapted to fit over an end of said receptacle. 
     
     
       4. The refueling check valve of claim 1 in which said by-pass valve includes a gasket and a Belleville spring which exerts a sealing load on said gasket. 
     
     
       5. The refueling check valve of claim 4 in which said gasket is comprised of a polyamide. 
     
     
       6. A refueling check valve assembly for a compressed natural gas vehicle comprising: a) a receptacle adapted to mate with a fuel supply nozzle, said receptacle including a filter for removing particulate matter from the fuel;   b) a valve body having first and second gas flow passages therethrough, the respective first ends of said first and second gas flow passages communicating with said receptacle, and the respective second ends of said first and second gas flow passages adapted to communicate with a fuel storage vessel; and   c) a check valve in said first gas flow passage of said valve body, said check valve being normally biased into a closed position to prevent the flow of gas through said first gas flow passage and which opens in response to a flow of fuel under pressure.   
     
     
       7. The refueling check valve of claim 6 including a by-pass valve in said second gas flow passage in said valve body, said by-pass valve being operable to permit a flow of gas from said fuel storage vessel through said receptacle. 
     
     
       8. The refueling check valve of claim 7 in which said by-pass valve includes a gasket and a Belleville spring which exerts a sealing load on said gasket. 
     
     
       9. The refueling check valve of claim 8 in which said gasket is comprised of a polyamide.